Mixed metal complex salts of phosphoric acid esters and mineral oil compositions containing the same



United States MIXED METAL COMPLEX SALTS OF PHOS PHORIC ACID ESTERS AND MINERAL OIL COMPOSI- TIONS CONTAINING THE SAME No Drawing. Application October 20, 1955 Serial N0. 541,848

20 Claims. (Cl. 252-325) This application is a continuation-in-part of copending application Serial No. 246,502, filed September 13, 1951, now abandoned.

This invention relates to improved lubricating oil compositions, particularly mineral lubricating oils for use in internal combustion engines.

As is well known, mineral lubricating oils refined for use as lubricants have a tendency to oxidize in use in an engine with attendant formation of oxidized products which are acidic in character and which exert a strong corrosive action on the engine parts, such as the hard metal alloy bearings. The oxidation of the oil also produces carbonaceous sludge deposits in the engine, particularly around the pistons and oil rings causing them to stick, thus materially lowering the efficiency of the engine.

To counteract these conditions, there have been developed in the art chemical agents which when added to a mineral lubricating oil designed for use in internal combustion engines, have the ability to inhibit or retard oxidation of the oil. These agents are designated as antioxidants. Other agents have been developed which have the ability to suspend the carbonaceous oxidation products formed in the oil, thereby keeping the engine parts clean and free from clogging and sticking effects normally encountered. These materials are known as detergents. The present invention is concerned with chemical additives which exhibit a two-fold ability, viz., (1) the ability to inhibit the formation of acidic, corrosive oxidation products in the oil during use in an engine and (2) the ability to keep the engine parts clean and free from sticking. These additives are, therefore, antioxidants as well as detergents. This two-fold action of these materials is, of course, of great advantage from an economic standpoint since ordinarily separate additives are employed to impart each of these characteristics to an oil.

It is, therefore, the object of this invention to provide a mineral lubricating oil composition which is stabilized against the formation of corrosive bodies therein during use and which is also fortified as to its detergent ability. Other and further objects will appear from the following detailed description of the invention.

The additives contemplated herein may be designated, broadly, as mixed-metal, zinc-containing, complex salts of partial esters of phosphoric acid. Due to the complex nature of these compounds, their exact chemical structures are not presently known.

Broadly, the complex salts of the invention are prepared by the method which comprises the steps of (1) reacting one mol of phosphorus pentoxide with from about one to about three mols of an organic hydroxy compound selected from the group consisting of a hydroxyaromatic compound that has an alkyl substituen-t having at least 8 carbon atoms in place of a nuclear hydrogen atom thereof and a primary, aliphatic alcohol having at least 8 carbon atoms per molecule, to form an acidic, partial ester of phosphoric acid, (2) reacting said acidic partial atent O 2,790,765 Patented Apr. 30, 1957 ester of phosphoric acid with a zinc salt reagent in an amount sulficient to furnish at least one equivalent of zinc per equivalent of acid-hydrogen content in said acidic, partial ester of phosphoric acid, and (.3) reacting the product obtained in step 2 with a metal hydroxide selected from the group consisting of calcium hydroxide, barium hydroxide, strontium hydroxide, cadmium hydroxide, magnesium hydroxide and cobalt hydroxide, in an amount sufficient to furnish at least one equivalent of metal per equivalent of acid-hydrogen content in said acidic, partial ester of phosphoric acid.

in the practice of the invention, the reaction of the partial ester with the metal salt reagent can be accomplished by first reacting about one equivalent of a zinc salt, such as zinc hydroxide, zinc carbonate, zinc alcoholate or a zinc carboxylate, followed by reaction with at least one equivalent of a metal hydroxide of a metal selected from calcium, barium, strontium, cadmium, magn'esium and cobalt. However, more than one equivalent of the zinc salt reagent, other than zinc hydroxide, can be used in the first reaction, say, up to and including two equivalents, or more, followed by reaction with at least an additional equivalent amount of the metal hydroxide other than zinc. It will be understood, therefore, that the one equivalent of each of the two different metal salts actually represents the minimum amounts of these reagents which can be employed. Alternatively, the reaction of the partial ester with the metal salt reagent can be conducted by utilizing at least about two equivalents of a zinc carboxylate reagent in the first reaction followed by reaction with at least an additional equivalent of a metal hydroxide reagent selected from the metal hydroxide of calcium, barium, strontium, cadmium, magnesium and cobalt. Here again, these amounts represent the minimum amounts of these reagents which can be used. Thus, althoughhigher amounts than those stipulated for the various reagents can be used, such amounts will provide no particular advantage. It can be said then that the upper limit with respect to the amounts of the several metal reagents is not a critical factor but is governed largely by practical considerations. Thus, for example, the use of large excess amounts of the metal reagents tends to reduce the fluidity of the reaction mass, thereby creating handling and filtration difficulties.

, The total amount of metal which is incorporated into the complex salts of the invention is usually from two to three times, or more, greater than that which would be contained in the normal salts of the partial esters. Due to their high metal contents, these mixed-metal complex salts possess superior properties as oil detergents over the normal salts. It will be appreciated that the complexsalts prepared by the use of two equivalents, or more, of a zinc carboxylate followed by reaction with an additional equivalent of metal hydroxide are actually complexes of complex zinc salts having an added metal contentof a different metal. The complex zinc salts are disclosed and claimed as mineral oil additives and as new compositions of matter in a copending application, Serial No. 541,849, filed October 20, 1955, in the name of Ferdinand 'P. Otto, one of the applicants herein.

It is recognized that normal salts of phosphoric .acid esters have been disclosed heretofore as oil additives, e. g., they are shown in U. S. Patents Nos. 2,228,658 and 2,228,659 to B. B. Farrington and No. 2,228,271 to George L. Neeley. However, as far as is known, there has been no disclosure in the art of mixed-metal complex salts of the character herein contemplated. Since these salts per se have not been known heretofore, they are claimed herein as new compositions of matter.

As previously stated, the reactions involved in the formation of the mixed-metal salts of the invention are complicated and the exact structure of these compounds have V not been determined. Theoretically, however, it is known, with respect to the phosphoric acid esters, that when an alkylated hydroxyaromatic compound, such as an alkylphenol (or a primary, aliphatic alcohol), reacts with phosphorus pentoxide in a mol ratio of 3:1, for example, the product consists essentially of a mixture of (l) monoalkaryl (or -alkyl) phosphoric acids, (2) di? alkaryl (or-alkyl) phosphoric acids and (3) pyrophosphoric acids. These compounds are represented by the following formulae in which R represents the organic substituent.

The mol ratio of the hydroxy reactant. to phosphorus pentoxide. would, of course, be expected to affect the relative proportions of these compounds present in the product mixture. When, for example, this mol ratio is 3: 1, the major components of the product. are believed to be the monoand di-esters of phosphoric acid with minor amounts of pyrophosphoric acid.

It has been found that when a normal, zinc salt of, for example, the octylphenol-phosphorus pentoxide (3:1) product is further reacted with a hydroxide of a metal such as calcium, barium, strontium, cadmium, cobalt or magnesium, a product salt is formed, which contains up to as many as three equivalents of total metal, including zinc, per equivalent of acidity in the octylphenolphosphorus. pentoxide product. As aforestated, the exact structure of such complex salt products is not known. However, it is believed that the extra equivalents of metal are incorporated into the molecule through a coordination or complexing of the metal hydroxide with like. Preference in general is to the monohydroxy phe' nols otherwise unsubstituted, particular preference being given to phenol and alpha and beta naphthol.

The hydroxyaromatic compound may have one or sev-- eral alkyl groups attached to the nucleus thereof. In any case, the alkyl portion of this compound should contain a total of at least 8 carbon atoms. Thus, if the alkyl substituent contains less than 8 carbon atoms, the aromatic nucleus should contain more than one such substituent to bring the carbon atom content of the side chains so attached to about 8 in order to provide ultimate complex salts which are completely oil-soluble. Ontheother hand, the hydrocarbon from which the alkyl group is derived may suitably contain up to 30 or even 40 carbon atoms. In fact, a highly suitable source of the alkyl substituent is petroleum wax whichv contains hydrocarbon molecules having from about 20 to about 30 carbon atoms and an average of about 24 carbon atoms per molecule. Other suitable alkyl hydroxyaromatic compounds are, for example, octylphenol, diamylphenol, decylphenol, laurylphenol, tetradecylphenol, hexadecylphenol and octadecylphenol, octylphenol being particularly preferred.

Where an aliphatic alcohol is used for reaction with the phosphorus pentoxide, rather than an alkaryl hydroxy compound, it should likewise contain at least about 8 carbon atoms and suitably as high as 20 or 30 carbon atoms. Of the alcohols suitable for use in the invention, there may be mentioned as non-limiting examples the following: octyl alcohol, nonyl, decyl, undecyl, dodecyl, tetradecyl, hexadecyl, octadecyl, carnaubyl, ceryl and melissyl alcohols. Unsaturated alcohols, such as oleyl alcohol, may also be used.

The various alkylphenols and aliphatic alcohols utilized in the invention, with the exception of the wax-alkylated phenols, are either available commercially or the methods for their preparation are within the skill of those versed in the art. The preparation of a wax-alkylated type of product, however, is illustrated by the following the normal zinc salt; of, the phosphoric acid ester. Thus, procedure.

the reaction of magnesium hydroxide with the normal zinc salt of the octylphenol-phosphorus pentoxide, product might, for example, occurs as follows:

ALKYL HYDROXYAROMATIC COMPOUND The preparation of the compounds of the invention involves, first, the alkylation of a hydroxyaromatic compound, such as phenol, i. e., where an alkarly phosphoric acid ester is desired. This may be accomplished by methods knownv to the art, such, as by a FriedelvCrafts synthesis using a halogenated hydrocarbon. The alkylation may also be eiiected by reaction of the aryl hydroxide nol resins, methyl-hydroxydiphenyl, gu aiacol, alpha and beta naphthol, alpha and beta methyl naphthol, tolyl naphthol, xylyl naphthol, benzyl naphthol, anthranol,

phenyl methyl naphthol, phenathrol, chlorphenol'andtlie WAX-PHENOL A parafiin wax melting at approximately F. and

predominantly comprised of hydrocarbons, having at least 20 and an average of about 24 carbon atoms in their molecules, is melted and heated to about 200 F., after which chlorineis bubbled therethrough until the wax has absorbed about 14%, by weight, of chlorine. A sufficient quantity of this chlorinated wax to provide three atomic proportions of chlorine is then heated to a temperature varying from just about its melting point to not over F; One mol of phenol (CeHsOI-I) is then mixed with the chlorowax. The mixture is then heated to about 150 F. and a quantity of anhydrous aluminum chloride, corresponding to about 3% of the weight of the chlorowax in the mixture, is slowly added with active stirring. The rate of addition of the aluminum chloride should be sutficiently slow to avoid violent foaming and during the addition the temperature should be held at about 150 F. After the aluminum chloride has been added, the temperature of the mixture may'be increased slowly over a period of 15 to 25 minutes to a temperature of about 250 F. and then should be more slowly increased to about 350 F. To control the evolution of HCl gas, the temperature of the mixture is preferably raised from 250 F. to 350 F. at a rate of approximately one degree per minute, the whole heating operation occupying approximately two hours from the time of adding the aluminum chloride. If the emission of HCl gas has not ceased when the final temperature is reached, the mixture may beheld at 350 F. for a short time to allow completion of the reaction. However, to avoid possible cracking of the wax, the mixture should not be heated appreciably above 350 F., nor should it be held at that temperature for any extended length of time.

It is important that all unreacted, or non-alkylated, phenol remaining in the reaction mixture, as well as aluminum chloride, be removed. This can be conveniently effected by washing the product several times with a mix- I ture of water and an alcohol, such as butanol, preferably at elevated temperature, say 175 F. The product may then be treated with steam. This latter step will insure complete removal of the unreacted material and also dry the product.

It will be understood that a wax-substituted phenol prepared according to the above procedure, in which a quantity of chlorowax containing three atomic proportions of chlorine and having a chlorine content of 14% is reacted with one mol of phenol, is designated as wax-phenol (3-14). Similarly, wax-phenol (3-10) and waxphenol (1-10) may also be prepared by the reaction of sufiicient amounts of chlorinated wax, containing 10% by weight of chlorine, to provide three atomic proportions and one atomic proportion of chlorine per mol of phenl, respectively, in the reaction and are useful in the invention. In general, the amount of chlorowax, containing from about 10% to 18% by weight. of chlorine, used in the reaction is sufiicient to supply between one and four atomic proportions of chlorine per mole of phenol used.

PARTIAL ESTER OF PHOSPHORIC ACID In preparing the phosphoric acid ester, the phosphorus pentoxide and the alkyl hydroxyaromatic compound, or alcohol, are heated together at a temperature of from about 50 C. to about 150 C. for a period of time to insure substantially complete reaction, usually from about 5 to 15 hours. An inert solvent, such as toluene, xylene or the like, may be used to facilitate the reaction. A mineral oil may also be conveniently used as the solvent, in which case the product is an oil concentrate which may be used directly in the preparation of the ultimate complex mixed-metal salt. In this way, the complex salt product is obtained in the form of an oil concentrate and may be utilized as such for addition to mineral lubricating oils. Where a solvent other than mineral oil is used, the reaction mixture is filtered and topped at elevated temperature and reduced pressure to remove the solvent.

The proportion of alkyl hydroxyaromatic compound, or alcohol, and phosphorus pentoxide used in the reaction can be varied between from about one to about three mols of the alkyl hydroxyaromatic compound, or alcohol, to one mol of phosphorus pentoxide, although our preferred products are obtained by the use of about three mols of the alkyl hydroxyaromatic compound (or alcohol) per mol of phosphorus pentoxide.

MIXED-METAL COMPLEX SALT As indicated previously, the mixed-metal complex salts can be prepared from the normal zinc salts of the partial esters of phosphoric acid by reaction with a metal hydroxide of the metals calcium, barium, strontium, cadmium, magnesium and cobalt. Mixedernetalcomplex. salts can also be made, however, without firstforming a.

normal salt, by first forming the complex zinc salt and then further complexing the complex zinc salt by reaction with one of the said metal hydroxides.

The reaction between the phosphoric acid ester and zinc salt reagent to form the normal zinc salt or the complex zinc salt and the reaction between either of these and the metal hydroxide to form the mixed-metal complex salt are accomplished at temperatures from about 50 C. to about 200 C. and are completed in a relatively short time, generally from about one-half hour to two hours. They may be carried out in a suitable solvent medium, such as benzene, toluene, xylene and the like, or a mineral oil may be used as the solvent.

As indicated previously, the amount of metal supplied to the reaction by the metal hydroxide when reacting it with either the normal zinc salt or the complex zinc salt should be sufiicient to supply at least one additional equivalent of metal to the reaction based on the acidhydrogen content of the partial ester used to make the normal salt. The amount of zinc acetate used to form the complex zinc salt, on the other hand, should be such as to supply at least two equivalents of zinc on the basis of the acid-hydrogen content of the partial ester used.

We have found that the formation of the mixed-metal complex salts is greatly enhanced by the presence in the reaction of a small amount of water in the reaction mixture.v We have also found that in forming the complex zinc acetate salt, it is convenient and economical to supply the zinc acetate to the reaction as zinc oxide and acetic acid.

A full understanding of the nature and manner of preparation of the mixed-metal complex salts of the invention and their utility as oil additives may be had from the following illustrative examples and test results.

Example 1 OCTYLPHENOL-PBOg; (3 2 1) PRODUCT Grams Reaction mixture:

Octylphenol 800 P205 180 Procedure.--The Octylphenol was placed in a 2 liter, 4-necked, round-bottom flask equipped with a reflux condenser, thermometer and mechanically driven stirrer and was heated to C. with agitation. The temperature was maintained at 100 C. :5" C. during portionwise addition of phosphorus pentoxide over a two-hour period and during the reaction period proper of eight hours duration. The clear light amber reaction product was filtered through filtering clay contained on a heated Buchner funnel. The product had an N. N. (neutralization number) of 210 and contained 7.99% phosphorus.

(3: 1) product and the mineral oil were placed in a 3-liter, 4-necked, round-bottom flask equipped with a reflux condenser, thermometer and mechanically driven stirrer. The zinc carbonate was added gradually over a 15-minute period and the mixture heated to and maintained at 100 C. for two hours. The reaction product was filtered through filtering clay contained on a heated Buchner fun- ,nel giving aproduct containing 3.90% zinc.

acid-refined Mid-Continentl) "grams; -400 Ca(-OH-)2 do' 25 H2O milliliters 75 Procedure-The zinc salt of octylphenol-phosphorus pentoxide 3:1) product was addedto a 1-liter, 4-necked, round-hottomflask equipped with a condenser, thermometer and. mechanically driven stirrer and. heated at 65 C. The. calcium hydroxide and waterwere. added as a slurry tothe. reaction flask. The water was removed by distillation with the. aidof a-nitrogenrflush. by heating to a temperature of 150 C. which was attained in two hours. After cooling.to 100 C., the filtering clay was added and the product filtered through filteringclay contained on a heated Buchner funnel. senting the finished product, contained 2.6% calcium and 4.26% zinc.

. Example 4 COMPLEX ZINC ACETATESAIHS OF OCTYLPHENOL-- P205 (3: 1) PRODUCT 1 Reaction mixture:

Octylphenol-PzOs (3:1) product (Ex. 1)

grams 400 Mineral oil (S. U. V. of 100 sec. at 100 F.,

acid-refined Mid-Continent) grams 800 Zn(C2H302)2.2H2O do 329 Ethyl alcohol, Formula30 1 "milliliters" 1450 A denatured alcohol containing 10 gallons of pure methanol per 100 gallonsrcf 190 proof. ethyl alcohol.

Procedure-The octylphenol-phosphorus pentoxide (3E1) product and the mineral oil were placed 'in a -liter, 4-necked, round-bottom -flask equipped with a reflux condenser, thermometer andmechanically driven stirrer and were heated with agitation to 70 C. The

wasdissolved in the Formula 30 alcohol and the solution was addedat 60 C. to the reaction flask. The'mixture was-then heated to 165 C. allowingralcohol andaqueous acetic acidto distill. After-three hours at this temperature; the last two hoursaunder diminished pressure, the reactiomproduct-was filtered through filtering clay containedxon a heated Buchner funnel. The filtrate containedI8.35% zinc and 2.73% phosphorus.

Example 5 COMPLEXED MAGNESIUIlI-ZINC ACETATE SALT OF OCTYLPHENOLP2O5 (3 2 1) PRODUCT Reaction mixture:

Complex zinc acetate salt of octylphenol-PzOs (3:1) product (Ex. 4) (containing 42% mineralaoil [S. U. V. of 100. sec. at 100 F.,

acid-refined Mid-Continentl) grams 600 Mg(OH)z do 57 H2O milliliters 200 Procedure-The zinc acetate salt of octylphenolphosphorus'pentoxide (3:1) product was addedto a-2-liter, 4-necked, round-bottom flask equipped with a condenser;

thermometerandmechanically' driven stirrer and heated to '35 C. The magnesium-hydroxide and water were added asqaslurry to -the-reaction-fiask. The-water was removed-by"distillation withtheaid of-a nitrogen flush-by heating toe-temperature of 165 C. The reaction mix ture-was then held at this temperature for one-half hom under diminished pressure. After cooling-tlie product- The filtrate, repre was ifiltered through filteringvclay contained on .a heated... Buchner: funnel. The filtrate; representing the finished product, contained 2.34% magnesium and 9.85% *ZlIlCl Procedure-The di-tert-amylphenol was placed in a 5-liter, 4-necked, round-bottom flask equipped with a.

reflux condenser, thermometer and mechanically driven stirrer. After heating to 100 C., phosphorus pentoxide was gradually added over a six-hour period. The reaction;

mixture was-then held between C. and C. for eight'hours to insure complete reaction. product was filtered through filtering clay contained on a heated Buchner funnel. The filtrate, representing the. finished product, contained 7.40% phosphorus and had an N. N. of 183.

Example 7 COMPLEXMAGNESIUM-ZINC ACETATE SALT OF DL PERT-AM'YLPHENOL-PaOs (3: 1) PRODUCT Reaction mixture:-

Di-tert-amylphenol-PiOs (3:1) product (similar to Ex. 6) "grams" 400 Mineral oil (SrU. V. of 100 sec. at 100 F.,

acid-'refined- Mid-Continent) "grams" 564- Zinc oxide .do 107 Aceticacid (glacial); do 158 Magnesium" hydroxide. do 76 H2O milliliters- 300 Pr0cedure.The di-tert-amylphenol-phosphorus pentioxide (3:1) product and mineral oil were mixed in a 2-liter, 4necked, flask equipped with a condenser, thermometer and mechanically driven stirrer. Acetic acid was addedfollowed by zinc oxide at room temperature and the reaction mixtureheatedto C., during the course'of which an aqueous acetic acid distillate was collected with theaid of a-nitrogen flush; The reaction mixture was thenheld at 155 C. to C. under diminished pressure for one hour. Upon cooling to 100 C. a slurry ofwater and magnesium hydroxide was added 1 and the-mixture heated to 165 C. during the course of'twohours aud held at this temperature for 1. hour under diminished pressure.

clay contained on a heated Buchner funnel. The filtrate,

representingthefinished product, contained 1.48% magnesium, 7.41% zinc. and 2.72% phosphorus.

Example 8 DODECYLPHENOL-PzOs (3 i 1) PRODUCT Reaction mixture: Grams Dodecylphenol 600 P20 102.5

Procedure.-The dodecylphenol was placed in a 1-liter, 4-necked, round-bottom flask equipped with a reflux condenser, a thermometer and a mechanically driven stirrer and was heated with agitation to 100 C. and then phosphorus pentoxide was added portionwise, keeping the tem peratureconstant, over-a two-hour period. The tom perature-ofthe reaction mixture was then'raised'to 150 C. and maintained at 150 C. for three hours. The

product 7 contained 6.43 phosphorus and possessed an The. reaction The reaction product was then cooled to 100 C. and" filtered through filteringc 9 Example 9 ooMPLnx "ZINC ACETATE SALT on DODEQY PHENOL- P205 (3 1) PRODUCT Reaction mixture:

Dodecylphenol-PzOs (3:1) product (N. N.=

Prcedure.-The dodecylphenol-phosphorus pentoxide (3:1) product-and mineral oil were mixed in a 2liter, 4-necked, round-bottom flask equipped with a thermometer, a Dean-Stark type distillation assembly, a submerged gas inlet tube, and a mechanically driven stirrer. Aqueous zinc acetate prepared by heating zinc oxide, acetic acid and water to 95 C. was added to the dodecylphenolphosphorus pentoxide (3:1)-oil mixture at 85 C. The reaction mixture was heated to 165 C. with removal by distillation of dilute aqueous acetic acid with the aid of nitrogen bubbled through the gas inlet tube. On attaining 165 C., the reaction mixture was held at that temperature for hour under atmospheric pressure and for /4 hour under diminished pressure to insure removal of acetic acid. The material was cooled to 100 C. and filtered through filtering clay contained on a heated Buchner funnel. The filtrate, representing the finished product, contained 7.27% zinc.

Example COMPLEXED MAGNESIUM-ZINC ACETATE SALT OF DODECYLPHENOL-PaOs (3 :1) PRODUCT Reaction mixture:

Acetate zinc salt of dodecylphenol-PzOa (3:1)

product (Ex. 9) grams 439 Mg(OH)2 do 32.8 H2O m 98.4

moved from the reaction by distillation'with the aid of a stream of nitrogen, the reaction temperature attaining 165 C. after dehydration. The reaction was maintained at 165 C. for one hour at atmospheric pressure and then cooled to 100 C. and filtered through filtering clay contained on a heated Buchner funnel. The filtrate, representing the finished product, contained 1.7% magnesium, 6.29%zinc and 2.49% phosphorus.

Example 11 C14 ALKYLPHENOL-PaOs (3: 1) PRODUCT Reaction mixture: Grams C14 alkylphenol 2 300 2 5 44.4

9 Oronite alkylphenol No. 1'4, 1;, mixture of monoalkylated phenols, consisting predominantly of para isomers, the alkyl groups of which are branch-chained and contain an average of about 14 carbon atoms.

Procedure-The C14 alkylphenol was placed in a 1-liter, 4-necked, round-bottom flask equipped with a reflux condenser, thermometer and mechanically driven stirrer and heated to 100 C. Phosphorus pentoxide was 10 Example 12 COMPLEX MAGNESIUM-ZINC Acumen earn? or Cu ALKYLPHENOL-PsOs a 1) rnonucr Reaction mixture:

C14 alkylphenol-P205 (3:1) product (Ex.

11) grams 536 Mineral oil (S. U. V. of sec. at 100 F.,

acid-refined Mid-Continent) grams Zinc oxide do 32.9 Acetic acid (glacial) do 48.7 Magnesium hydroxide do 23.6 H2O ml 176 Pr0cea'ure.-The procedure was the same as that for Example 7. The product contained 1.33% magnesium, 5.63% zinc and 2.33% phosphorus.

Example 1 3 WAX-PHENO'L (3-14) -Pa0s (3 2 1) PRODUCT Reaction mixture: Grams Wax-phenol (3-14) 1000 Mineral oil (S. U. V. of 296 sec. at 100 F.,

solvent-refined Penna oil) 2000 60 NORMAL ZINC SALT OF WAX-PHENOL (314)-Ps0s (3 1) Reaction mixture: Grams Wax-phenol (3--14)-P205 (3 1) product (similar to'Ex. 13, N. N.=17.6) 1000 ZnO 12.7 HCzHzOz (glacial) 18.6 H2O 31.6

Pro'cedare.--'Ihe wax-phenol (314)-phosphorus pentoxide (3:1) product was placed into a 3-liter, 4-necked, round-bottom flask equipped with a thermometer, a submerged gas inlet tube, a Dean-Stark type distillation assembly and a mechanically driven stirrer. Zinc oxide, acetic acid and water were heated to 95 C. to. form an aqueous solution of zinc acetate which was added to the wax-phenol v(3-14)-phosphorus pentoxide (3:1) product at 70 C. The reaction mixture was heated with agitation to C. with recovery of aqueous acetic acid condensate and then reacted at 165 C. for hour at atmospheric pressure followed by like treatment under diminished pressure for hour to insure complete removal of acetic acid. This product was utilized in the unfiltered condition as the intermediate in Example 15.

Example 15 COMPLEX BARIUM-ZINO SALT on WAX-PHENOL 344 P205 3:1 PRODUCT Reaction mixture: Grams Zinc salt of wax-phenol (3-14)-P2O5 (3:1)

product (Ex. 14) 500 Ba(OH)z.8H2O 49.5 H2O 50.0

Pr0cedure.-The zinc salt of wax-phenol (3-14) -phosphorus pentoxide (3:1) product was placed into a 1-liter,

4-necked, round-bottom flask equipped with a thermometer, a submerged gasinlet tube, a Dean-Stark type disstillation assembly and a mechanically driven stirrer, and

Example 16 WAX PHENOL (3-14)P:Oa-(3 1) PaRODUCT Reaction "mixture."

Wax+phenol (3 14) (phenol'content=approx;

11.9%) grams 300' P205 do 18 Toluene m 300 Procedure.The wax-phenol (3-14) and toluene were placed in a 2-liter, 4-necked, round-bottom flask containing a' 'reflux' condenser; thermometer and mechanically driven stirrer. Afterheating to 100 C.', phosphorus pentoxide-was-gradually'added'to the mixture over a four-hourperiod. Followingthis, the temperature of thermixturenwasheldiat- 100? C. forxazperiod ofeight hourskto insurecomplete reaction. The product was then filtered through filtering. clay and the filtrate was topped to 150 C. under diminished pressure to remove: the toluene solvent. The-residue; vrepresenting the finished-product,. contained 2.2%i phosphorusrandhad 'a N. N. of 48.

Example 17 NORMA-LZIN'C. SALT OF-W'AX-P-HENOL (3 14)-POs (3': 1) PRODUCT? Reaction mixture:

Wax-phenol (314)'-P2O5-(3:1) product (Ex.

P rcerlure.-'Ihe wax-phenol (3-14)-,phosph'orus pentoxide 3:1 product and the mineral oil.were..placediin a 2-liter, 4-necked, round-bottom flask equipped with. a refiuxcondenser, thermometer anda mechanicallydriven. stirrer. Theizinc acetate diI-hydratewas dissolved in the. eth'ylalcohol and "the solution added to the other reactant. at room temperature. The reaction mixture was heated; removing ialcohol by distillation to 175 C.',- and .held. at that temperature forone hour. After cooling thereaction-product was dissolved "in benzene and the: solution; filtered "through a Buchner funnel packed with filtering clay; The zinc salt was recovered as the distillation. residue by topping to 175 CIunder diminished pressure. This. material contained0.78% zinc and 0.52% pliesph orus:

Example 18.

COMPLEXWZINC .ACETALUE LSALT OF WAX PHENOIw (314) P:Ou (3:1) PRODUCT Reaction mixture: 7

. Wa'x-phenol-i (S -14) PiOB (3: l) product (Ex;

13) grams 400 Zn(C2H302)2.2H2O .do; 30.6 Ethyl alcohol, Formula 30.. ml 175 Procedure-The"wax-phenol '(3-l4)-'phosphorus :pentoxide- (3 .-1)-pror.luctwas-addedto a l-litr, 4-necked, round-bottom --flask equipped" with a' reflux condenser, thermometer andrmechanically-driverr stirrer.. Thee-zinc acetate di hydr'ate. was dissolved-in 1Formula'k30fl alcohol? and ".th'ejsolution added ..to the reaction. flask: at: 60? C. The: reaction-.mixture-was. heated with. agitation; and a. nitrogeirfliish tov remove alcohol and; aqueous-acetic acid 1.

and then held at the attained temperature of 165 C. under. diminished. pressuretor. one .hour. product was cooled' toffl"Cl,l filtering clay added, and the product filtered through filtering clay. on'a heated Buchner funnel. 'Ihefiltratmrepresenting. the finished product, wasadarlc amber liquid containing 2.64% zinc and 0.75 phosphorus.

Example 19 COMPLEXED BARIUM-ZINC ACETATE SALT 0F WAX- PHENOL (3-14) -Pn0s -(3 1) PRODUCT Reaction mixture:

Complexed' zinc acetate salt of wax-phenol (3-14)-PaO5 (3:1) product (similar to'Ex. 18) (containing 63%' mineral oil S.'U. V. of sec. at100' F acid refined Mid-Confi Pr0cedure.The zinc acetate salt of wax-phenol (3-14)-phosphorus pentoxide (3:1) product was added toa Z-liter, 4-necked, round-bottom flask equipped with Example. 20.

OCENOL-PBOB (3: 1) PRODUCT Reaction mixture: Grams Ocenol (octadecenol) 536 P 20510 94.6

Proeedure.T-He ocenol was placed in a 1-liter, 4- necked, round-bottomfiaslc equipped with a reflux condenser, a thermometer, and a mechanically driven stirrer, and was heated to 85 'C. The phosphorus pentoxide was added portionwise at 15-minute intervals over a two-hour period; After completion =of tlie phosphorus pentoxide addition; the reaction" mixture was heated to' and maintained at 100"' 0. with agitation for eight hours. The product, a'viscousamber'colored liquid; had a poten tiometric N. NUOf'1962' Example 21 COMPLEX MAGNESIUM-ZINCSALT or ocnn'on-noi I (a: 1) Pnonucu Pfocedure.---The ocenol-phosphorus Y pentoxide (3 1 product and the dilution oil were placed ina 500-1111., 4-

necked, round-bottom flask equipped with a distillation assembly, asubmerged'gas inlet tube, a thermometer and a mechanically, driven stirrer. After heating the-mixture to'70 (2., aqueous zinc acetate, prepared from heating zincroxide; aceticacid and water 'to'90'C., was added directly 'and'heating was increased and nitrogen bubbled throught'the mixture removing "aqueous acetic acid' by distillation; The :temperature rose=to 165 'C. in one hour andxtheereactiomwas continued for an additional onehalfihourzunder diminished'pressure to insure 'removal of 75iaacetic acid. On. cooling-to 80 0, anaqueousslu'rryflf The reaction EVALUATION OF PRODUCTS In order to determine the suitability of the mixed-metal complex salts of the invention as detergents and antioxidants in lubricating oils, oil blends of the various complex salt products described herein were prepared and subjected to engine tests. The test used was the Lauson detergency test D-4. The results of these tests are summarized in Table I. As seen from the table, the mixedmetal complex salts greatly improve the detergent and antioxidant character of the oil.

LAUSON DETERGENCY TEST D-4 This test determines the eflfectiveness of the lubricating oil in preventing fouling as measured by the cleanliness of rings, lands, ring grooves and piston skirts. Cleanliness ratings are based on a scale of from 100 to 0, a 100 rating signifying a perfectly clean condition and a rating representing the worst possible deposit condition. Bear ing Weight loss is also measured as supplemental data.

A single cylinder, 4-cycle, liquid cooled Lauson engine with splash lubrication and having a copper-lead bearing is used. The operating conditions are as follows:

Oil temperature F 220 Iackettemperature F 275 Speed R. P. M 1825 Brake load H. P 1.6

One-half throttle. 13-1 air-fuel ratio. Oil added every 20 hours (one gallon sample used).

The engine is inspected at the end of 20, 60 and 100 hours, the duration of the test being 100 hours. The fuel used is a controlled Mobilgas Special" type blend gasoline (40% thermal+30% catalytically cracked+30% straight run+2.5 cc. TEL/gal.).

For ready comparison, the metal and phosphorus contents of the various mixed metal complex salts prepared and tested as described herein are shown in Table II. It will be seen that the phosphorus contents of the complex salts are about the same as the corresponding normal zinc salts, but that the metal content of the complex salts are much greater, generally at least about twice that of the normal salts.

TABLE I Lauson D-4 Piston Detergency Test (S. A. E. 20 Base 011) Percent Example Percent Additive, Piston Cleanliness Used Oil Bearing Wt. Loss No. Product Additive Oil Free (CU-PB) Basis 20 hours hours 100 N. N. K. V. Top, G. Bottom,

hours 210 F. G.

Non 69 68 58 2.8 12.14 .290 .308 2 Nc i rmgl glue Salt oi Octylphenol-HO: (3:1) 2.8 1.0 78 69 63 2.3 10. 48 .067 .063

ro uc 3 Complex Calcium-Zinc Salt of Octylphenol- 1.8 1.0 85 80 78 3.3 11.42 .232 .163

P10; (3:1) Product. 5 Complexed Magnesium-Zinc Acetate Salt of 1.6 1.0 87 82 79 1.8 11.12 .161 .125

Octylphenol-P m (3:1) Product. 7 Complex Magnesium-Zinc Acetate Salt of di- 1.0 0.5 87 82 78 3.4 11.73 .160 .148

tert-amylphenol-PzO (3:1) Product. 10 Complex Magnesium Zinc Acetate Salt of 1.7 1 0 88 84 80 3.4 10.39 .154 .141

Dodecylphenol-PrO; (3:1) Product. 12 Complex Magnesium-Zinc Acetate Salt of C14 0.85 0.5 88 80 1.7 10.35 .058 .059

Alkylpheuol-PuO a (3:1)lProduct. 17 Normal Zinc Salt of Wax-Phenol (3-14)-Pr05 4.0 1.0 84 76 73 2.7 11.6 .313 .299

(3:1) Product. Barium-Zinc Salt of Wax-Phenol (3-10-1505 2.6 1.0 92 86 81 4.3 12.27

(3:1) Product. Complexed Barium-Zinc Acetate Salt of Wax- 2.5. 1.0 87 73 2.5 12.15 .126 .169

Phenol (314)P2Os (3:1) Product. Complex Magnesium Zinc Acetate Salt of 1.8 1.0 92 87 83 5.6 11.33 .189 .189

Ocenol-PzOa (3:1) Product.

1 S. A. E 20 Grade Solvent-Refined Penna 011:

K. V. 100 F 66. 99 K. V. 210 F 8. 69 N. N Nil TABLE 11 Theoretical Percent Percent Phosphorus Percent Actual Example Product Metal Percent Equiv- No. For et alents in Normal Excess of Theory Actual Salt Theory Complex Calcium-Zine Salt of octylphenol-Pros (3:1) Zn-4. 26

Product. Zn-5. 70 Ca2. 60 48 Complex Magnesium-Zinc Acetate Salt of Octylphenol- Zn9.85

P205 (3:1) Product. 211-5. 70 Mg--2. 34 182 3. 45 3. 38 Complex Magnesium-Zinc Acetate Salt of di-tert-amyl- Zn-7. 41

phenol-P10 (3:1) Product. Z11-4. 23 Mg1.48 257 2. 62 2. 72 Complex Magnesium-Zinc Acetate Salt o1 Dodecyl- Zn-6.

phenol-P205 (3:1) Product. Zn-4. 02 Mg1. 74 172 2.82 2. 49 Complex Magnesium-Zinc Acetate Salt 0! C14 Alkyl- Zn-5. 63

phenol-P 05 (3:1) Product. ZI14.09 Mg1.33 209 2. 35 2. 33 Barium-Zinc Salt of Wax-Phenol (3-14)-P205 (3:1) Prod- Zn-0. 81

not. Zn-O. 96 Ba-S. 1 139 0. 81 0. 67 Complex Barium-Zinc Acetate Salt of Wax-Phenol-PzOs Zn1.87

(3 1) Produ t, Zn-O. 95 Ba-3. 32 262 0.66 0.55 Complex Magnesium-Zinc Salt of Ocenol-PzOr (3:1) Zn-4. 79

Product. Zn-5. 4 Mg-1. 1 45 2. 3. 04

the usual amount beingfrorn about 0.25 to about weight percent, i. e., on an oil-free basis.

As indicated hereinbefore, the products of the invention may be made'up in the form of oil concentrates. These concentrates will contain, as a rule, amounts of additivesranging from upwards of about weight percent of the complex metal salt to thehighest soluble concentration of the salt in the oil.

The compounds of this invention may be used in lubrieating oil compositions containing other additives designed to improve the oil in different respects, e. g., E. P. agents, pour point depressants, V. I. improvers, defoamants, etc. The'additives of the inventionmay also be usedin oil in cornbinationwith'othertantioxidants and/ or detergents.

While the preparation andiuti-lity of certain specific representative compounds have been' described in detail herein, it is not intended that the invention be limited in any way thereby, but that it include such..variations in procedures and such products as come within the spirit and scope of the accompanyingclaims.

What is claimed:

1. A mineral lubricatingoil containingv a minor'proportion, suificient to improve the detergent character thereof, of a mixed-metal, zinc-containing complex salt of a partial ester of phosphoric acid having a metal content greater than that which would beequivalenttothe acid-hydrogen content of said partial ester prepared by the steps of (l) reacting one mol of phosphorus pentoxide with from about one to about threemols of an organic hydroxy compound selected from the group consisting of a hydroxy-aromatic compound that has an alkyl substituent having at least 8 carbon atoms in place of a nuclear hydrogen atom thereof anda primary, aliphatic alcoholhaving at least 8 carbon atoms per molecule, to form an acidic, partial ester of phosphoric acid, (2) reacting said acidic, partial ester of phosphoric acid with a zinc salt reagent in an amount suflicient to furnish at least one equivalent of zinc per equivalent of acid-hydrogen content in said acidic, partial ester of phosphoric acid, and

( 3) reacting the product obtained in step 2 with a metal hydroxide selected from the groupconsisting of calcium.

hydroxide, barium hydroxide, strontium hydroxide, cadmium hydroxide, magnesium hydroxide and cobalt hydroxide, in an amount sufiicient to furnish at least one equivalent of metal per equivalent of acid-hydrogen content in said acidic, partial ester of phosphoric acid.

2. A mineral lubricating oil'containing a minor proper tion, suflicient to improve the detergent character thereof, of a mixed-metal, zincand calcium-containing complex salt of a partial ester of phosphoric acid. having a metal. content greater than that which would be'equivalent to the acid-hydrogen content of said partial ester prepared by the steps of (l) reacting one mol of phosphorus pentoxide ofzinc per equivalent of acid-hydrogen contentinsa'id' partial ester, and 3) reacting theproduct of step 2 with calciumhydroxide inan amount suiiicient to provide about oue equivalent of calcium per equivalent of acid-hydrogen in said partial ester.

3. A mineral lubricating oil containing a minor proportion, sufiicient to improve the detergent character phoruspentoxide with about three mols of octylphenol, to form an acidic, partial ester of phosphoric acid, (2) reacting, said partial ester with an amount of zinc can bonate to provide about one equivalent of zinc per equivalent of acid-hydrogen content in said partial ester, and (3) reacting the product of step 2 with calcium'hydroxide in an. amount sufiicient to provide about one equivalent of calcium per equivalent of acid-hydrogen in said partial ester.

4. A mineral lubricating oil containing a minor proportion, sufilcient to improve the detergent character thereof, of 'a'mixed-metal, zinc-containing complex salt ofa partial ester of phosphoric acid having a metal content greater-than .that which would be equivalent to the acid-hydrogen content of said partial ester, prepared by the steps :of l) reacting one mol of phosphorus pcntoxidc' with from about one to about three mols of a hydroxy compound selected from a hydroxyaromatic compound having an allryl substituent of at least 8 carbon atoms in place of a nuclear hydrogen atom thereof and a primary,

aliphatic alcohol, to form an acidic, partial ester of phosphoric acid, (2) reacting the partial ester formed in step 1 with an amount of zinc acetate sufiicient to supply to the reaction at least about twoequivalents of zinc per equivalent of acid-hydrogen content in said partial ester, to form a complex zinc acetate salt of saidpartial ester,

and (3) reacting, the complex zinc acetate salt formed metal at least equivalent to the acid-hydrogen content of equivalent to theacid-hydrogen content of said partial ester, prepared by the steps of (1) reacting one mol of phosphorus pentoxide with from about one to about three mols of a hydroxyaromatic compound having an alkyl substituent of at least 8 carbon atoms in place of a nuclear hydrogen atom thereof, to form an acidic, partial ester of phosphoric acid, (2) reacting the partial ester formed in step 1 with an amount of zinc acetate sufiicient to supply tothe reaction at least about two equivalents of zinc per equivalent of acid-hydrogen content in said partial ester, to form a complex zinc acetate salt of said partial ester, and (3) reacting the complex zinc acetate salt formed in step 2 with an amount of magnesium hydroxide sutficient' to supplyto the reaction an amount of magnesium at least equivalent to the acid-hydrogen content of said partial ester of phosphoric acid.

-6.- A-minerallubricating oil containing a minor proportion, sufiic'ient to improve the detergent character thereof, of a mixed-metal, zincand magnesium-containing complex salt of a partial ester of phosphoric acid having a metal content greater than that which would be equivalent to the acid-hydrogen content of said partial ester, prepared by'the .steps of (l) reacting onernol of phosphorus pentoxide with about three mols of C14 alkylphenol, to form an acidic, partial ester of phosphoric acid, (2) reactingth'e partial ester formed in step 1 with an amount of zinc acetatesufiicient to supply to the reaction at least about two' equivalents of zinc per equivalent of acid-hythereof, of a mixed-metal, zinc= and calcium-containing complex salt of a partial ester of phosphoric acid having a metal content greater than that which would be equivalent to the acid-hydrogen content of said partialmester, prepared bythe steps of (1) reacting one mol of phosdrogen content in :said partial ester, to form a complex zinc acetate salt of said partial ester, and (3) reacting the complexzinc' acetate salt formedin step 2 with an amount of magnesium hydroxide sufficient to supply to ihereaction an amount of magnesium, at least equivalent to the acid-hydrogen content of said partial ester of phosphoric acid.

7. A mlncral lubricatingoil containing a minor proportron, sufficient to improve the detergent character thereof,

of a mixed-metal, zincand magnesium-containing complex salt of a partial ester of phosphoric acid having a metal content greater than that which would be equivalent to the acid-hydrogen content of said partial ester, prepared by the steps of 1) reacting one mole of phosphorus pentoxide with about three mols of C14 alkylphenol, to form an acidic, partial ester of phosphoric acid, (2) reacting the partial ester formed in step 1 with an amount of zinc acetate sufficient to supply to the reaction at least about two equivalents of zinc per equivalent of acid-hydrogen content in said partial ester, to form a complex zinc acetate salt of said partial ester, and (3) reacting the complex zinc acetate salt formed in step 2, in the presence of water, with an amount of magnesium hydroxide sufficient to supply to the reaction an amount of magnesium at least equivalent to the acid-hydrogen content of said partial ester of phosphoric acid.

8. A mineral lubricating oil containing a minor proportion, suliicient .to improve the detergent character thereof, of a mixed-metal, zincand magnesium-containing complex salt of a partial ester of phosphoric acid having a metal content greater than that which would be equivalent to the acid-hydrogen content of said partial ester, prepared by the steps of (1) reacting one mol of phosphorus pentoxide with about three mols of di-tertiaryamyl-phenol, to form an acidic, partial ester of phosphoric acid, (2) reacting the partial ester formed in step 1 with an amount of zinc acetate sufiicient to supply to the reaction -at least about two equivalents of zinc per equivalent of acid-hydrogen content in said partial ester, to form a complex zinc acetate sale of said partial ester, and (3) reacting the complex Zinc acetate salt formed in step 2 with an amount of magnesium hydroxide suflicient to supply to the reaction an amount of magnesium at least equivalent to the acid-hydrogen content of said partial ester of phosphoric acid.

9. A mineral lubricating oil containing a minor proportion, suflicient to improve the detergent character thereof, of a mixed-metal, zincand magnesium-containing complex salt of a partial ester of phosphoric acid having a metal content greater than that which would be equivalent to the acid-hydrogen content of said partial ester, prepared by the steps of (1) reacting one mol of phosphorus pentoxide with from about one to about three mols of an aliphatic alcohol having at least 8 carbon atoms, to form an acidic, partial ester of phosphoric acid, (2) reacting the partial ester formed in step 1 with an amount of zinc acetate suflicient to supply to the reaction at least about two equivalents of zinc per equivalent of acid-hydrogen content in said partial ester, to form a complex zinc acetate salt of said partial ester, and (3) reacting the complex zinc acetate salt formed in step 2 with an amount of magnesium hydroxide suflicient to supply to the reaction an amount of magnesium at least equivalent to the acid-hydrogen content of said partial ester of phosphoric acid.

10. A mineral lubricating oil containing a minor proportion, sufiicient to improve the detergent character thereof, of a mixed-metal, zincand magnesium-containing complex salt of a partial ester of phosphoric acid having a metal content greater than that which would be equivalent to the acid-hydrogen content of said partial ester, prepared by the steps of (1) reacting one mol of phosphorus pentoxide with about three mols of ocenol, to form an acidic, partial ester of phosphoric acid, (2) reacting the partial ester formed in step 1 with an amount of zinc acetate suflicient to supply to the reaction at least about two equivalents of zinc per equivalent of acid-hydrogen content in said partial ester, to form a complex zinc acetate salt of said partial ester, and (3) reacting the complex zinc acetate salt formed in step 2 with an amount of magnesium hydroxide sufiicient to supply to the reaction an amount of magnesium at least equivalent to the acid-hydrogen content of said partial ester of phosphoric acid.

11. As a new composition of matter, a mixed-metal, zinc-containing complex salt of a partial ester of phos' phoric acid having a metal content greater than that which would be equivalent to the acid-hydrogen content of said partial ester prepared by the steps of (1) reacting one mol of phosphorus pentoxide with from about one to about three mols of an organic hydroxy compound selected from the group consisting of a hydroxyaromatic compound that has an alkyl substituent having at least 8 carbon atoms in place of a nuclear hydrogen atom thereof and a primary, aliphatic alcohol having at least 8 carbon atoms per molecule, to form an acidic, partial ester of phosphoric acid, (2) reacting said acidic, partial ester of phosphoric acid With a zinc salt reagent in an amount suflicient to furnish at least one equivalent of zinc per equivalent of acid-hydrogen content in said acidic, partial ester, and phosphoric acid, and (3) reacting the product obtained in step 2 with a metal hydroxide selected from the group consisting of calcium hydroxide, barium hydroxide, strontium hydroxide, cadmium hydroxide, magnesium hydroxide and cobalt hydroxide, in an amount sutfiicient to furnish at least one equivalent of metal per equivalent of acid-hydrogen content in said acidic, partial ester of phosphoric acid.

12. As a new composition of matter, a mixed-metal, zincand calcium-containing complex salt of a partial ester of phosphoric acid having a metal content greater than that which would be equivalent to the acid-hydrogen content of said partial ester prepared by the steps of (1) reacting one mol of phosphorus pentoxide with from about one to about three mols of a hydroxy-aromatic compound having an alkyl substituent of at least 8 carbon atoms in place of a nuclear hydrogen atom thereof, to form an acidic, partial ester of phosphoric acid, (2) reacting said partial ester with an amount of zinc carbonate sufiicient to provide about one equivalent of zinc per equivalent of acid-hydrogen content in said partial ester, and (3) reacting the product of step 2 with calcium hydroxide in an amount sufiicient to provide about one equivalent of calcium per equivalent of acid-hydrogen in said partial ester.

13. As a new composition of matter, a mixed-metal, zincand calcium containing complex salt of a partial ester of phosphoric acid having a metal content greater than that which would be equivalent to the acid-hydrogen content of said partial ester, prepared by the steps of (l) reacting one mol of phosphorus pentoxide with about three mols of octylphenol, to form an acidic, partial ester of phosphoric acid, (2) reacting said partial ester with an amount of zinc carbonate to provide about one equivalent of zinc per equivalent of acid-hydrogen content in said partial ester, and (3) reacting the product of step 2 with calcium hydroxide in an amount suflicient to provide about one equivalent of calcium per equivalent of acid-hydrogen in said partial ester.

14. As a new composition of matter, a mixed-metal, zinc-containing complex salt of a partial ester of phosphoric acid having a metal content greater than that which would be equivalent to the acid-hydrogen content of said partial ester, prepared by the steps of (l) reacting one mol of phosphorus pentoxide with from about one to about three mols of a hydroxy compound selected from a hydroxyaromatic compound having an alkyl substituent of at least 8 carbon atoms in place of a nuclear hydrogen atom thereof and a primary, aliphatic alcohol, to form an acidic, partial ester of phosphoric acid, (2) reacting the partial ester formed in step 1 with an amount of zinc acetate suflicient to supply to the reaction at least about two equivalents of zinc per equivalent of acid-hydrogen content in said partial ester, to form a complex zinc acetate salt of said partial ester, and (3) reacting the complex zinc acetate salt formed in step 2 with an amount of a metal hydroxide, the metal substituent of which is selected from the group consisting of calcium, barium, strontium, cadmium, magnesium and cobalt, sufficientto supply to the reaction an amount of metal at least equivalent to the acid-hydrogen content of said partial ester of phosphoric acid.

15. 'As a new composition of matter, a mixed-metal, zincand magnesium-containing complex salt of a partial ester of phosphoric acid having a metal content greater than that which would be equivalent to the acid-hydrogen content of said partial ester, prepared by the steps of (1) reacting one mol of phosphorus pentoxide with from about one to about three mols of a hydroiij' aromatic compound having an alkyl substituent of at least 8 carbon atoms in place of a nuclear hydrogen atom thereof, to form an acidic, partial ester of phosphoric acid, (2) reacting the partial ester formed in step 1 with an amount of zinc acetate sutficient to supply to the reaction at least about two equivalents of zinc per equivalent of acid-hydrogen content in said partial ester, to form a complex zinc acetate salt of said partial ester, and (3) reacting the complex zinc acetate salt formed in step 2 with an amount of magnesium hydroxide sutficient to supply to the reaction an amount of magnesium at least equivalent to the acid-hydrogen content of said partial ester of phosphoric acid.

16. As a new composition of matter, a mixed-metal, zincand magnesium-containing complex salt of a partial ester of phosphoric acid having a metal content greater than that which would be equivalent to the acid-hydrogen content of said partial ester, prepared by the steps of (1) reacting one mol of phosphorus pentoxide with about three mols of C14 alkylphenol, to form an acidic partial ester of phosphoric acid, (2) reacting the partial ester formed in step 1 with an amount of zinc acetate suifi cient to supply to the reaction at least about two equivalents of zinc per equivalent of acid-hydrogen content in said partial ester, to form a complex zinc acetate salt of said partial ester, and (3) reacting the complex zinc acetate salt formed in step 2 with an amount of magnesium hydroxide suflicient to supply to the reaction an amount of magnesium at least equivalent to the acid hydrogen content of said partial ester of phosphoric acid.

17. As a new composition of matter, a mixed-metal, zincand magnesium-containing complex salt of a partial ester of phosphoric acid having a metal content greater than that which would be equivalent to the acid-hydrogen content of said partial ester, prepared by the steps of (l) reacting one mol of phosphorus pentoxide with about three mols of C14 alkylphenol, to form an acidic, partial ester of phosphoric acid, (2) reacting the partial ester formed in step l with an amount of zinc acetate sufiicient to supply to the reaction at least about two equivalents of zinc per equivalent of acid-hydrogen content in said partial ester, to form a complex zinc acetate salt of said partial ester, and (3) reacting the complex Zinc acetate salt formed in step 2, in the presence of water, with an amount of magnesium hydroxide sufficient to supply to the reaction an amount of magnesium at least "equivalent to the acid-hydrogen content of said partial ester of phosphoric acid.

18. As a new composition of matter, a mixed-metal,

Zincand magnesiam-containing complex salt of a partial ester of phosphoric acid having a metal content greater than that which would be equivalent to the acid-hydrogen content of said partial ester, prepared by the steps 01'' 1) reacting one mol of phosphorus pentoxide with about three mols of di-tertiary-amylphenol, to form an acidic, partial ester of phosphoric acid, (2) reacting the partial ester formed in step 1 with an amount of zinc acetate suificient to supply to the reaction at least about two equivalents of zinc per equivalent of acidhydrogen content in said partial ester, to form a complex zinc acetate salt of said partial ester, and (3) reacting the complex zinc acetate salt formed in step 2 with an amount of magnesium hydroxide sufficient to supply to the reaction an amount of magnesium at least equivalent to the acid-hydrogen content of said partial ester of phosphoric acid.

19. As a new composition of matter, a mixed-metal, zincand magnesium-containing complex salt of a partial ester of phosphoric acid having a metal content greater than that which would be equivalent to the acid-hydrogcn content of said partial ester, prepared by the steps of 1) reacting one mol of phosphorus entoxide with from about one to about three mols of an aliphatic alcohol having at least 8 carbon atoms, to form an acidic, partial ester of phosphoric acid, (2) reacting the partial ester formed in step 1 with an amount of zinc acetate sutT- cient to supply to the reaction at least about two equivalents of zinc per equivalent of acid-hydrogen content in said partial ester, to form a complex zinc acetate salt of said partial ester, and (3) reacting the complex zinc acetate salt formed in step 2 with an amount of magnesium hydroxide suilicient to supply to the reaction an amount of magnesium at least equivalent to the acidhydrogen content of said partial ester of phosphoric aei l.

20. As a new composition of. matter, a n'iixedanetai, zinc and magnesium-containing complex salt of a partial ester of phosphoric acid having a metal content greater than that which would be equivalent to the acid-hydrogen content of said partial ester, prepared by the steps of (l) reacting one mol of phosphorus pentoxide with about three mols of ocenol, to form an acidic, partial ester of phosphoric acid, (2) reacting the partial ester formed in step l with an amount of zinc acetate sufiicient to supply to the reaction at least about two equivalents of zinc per equivalent of acid-hydrogen content in said partial ester, to form a complex zinc acetate salt of said partial ester, and (3) reacting the complex zinc acetate salt formed in step 2 with an amount of magnesium hydroxide suiticient to supply to the reaction an amount of magnesium at least equivalent to the acid-hydrogen content of said partial ester of phosphoric acid.

References Cited in the file of this patent UNZTED STATES PATENTS 2,228,659 Farrington Jan. 14, 194l 2,346,155 Denison Apr. ll, 194-4 2,378,800 Amott June 19, 1945 2,745,863 Otto May 15, 1956 

1. A MINERAL LUBRICATING OIL CONTAINING A MINOR PROPORTION, SUFFICIENT TO IMPROVE THE DETERGENT CHARACTER THEREOF, OF A MIXED-METAL, ZINC-CONTAINING COMPLEX SALT OF A PARTIAL ESTER OF PHOSPHORIC ACID HAVING A METAL CONTENT GREATER THAN THAT WHICH WOULD BE EQUIVALENT TO THE ACID-HYDROGEN CONTENT OF SAID PARTIAL ESTER PREPARED BY THE STEPS OF (1) REACTING ONE MOL OF PHOSPHORUS PENTOXIDE WITH FROM ABOUT ONE TO ABOUT THREE MOLS OF AN ORGANIC HYDROXY COMPOUND SELECTED FROM THE GROUP CONSISTING OF A HYDROXY-AROMATIC COMPOUND THAT HAS AN ALKY SUBSTITUENT HAVING AT LEAST 8 CARBONATOMS IN PLACE OF A NUCLEAR HYDROGEN ATOM THEREOF AND A PRIMARY, ALIPHATIC ALCOHOL HAVING AT LEAST 8 CARBON ATOMS PER MOLECULE, TO FORM AN ACIDIC, PARTIAL ESTER OF PHOSPHORIC ACID WITH A ZINC SALT ACIDIC, PARTIAL ESTE OF PHOSPHORIC ACID WITH A ZINC SALT REAGENT IN AN AMOUNT SUFFICIENT TO FURNISH AT LEAST ONE EQUIVALENT OF ZINC PER EQUIVALENT OF ACID-HYDROGEN CONTENT IN SAID ACIDIC, PARTIAL ESTER OF PHOSPHORIC ACID, AND (3) REACTING THE PRODUCT OBTAINED IN STEP 2 WITH A METAL HYDROXIDE SELECTED FROM THE GROUP CONSISTING OF CALCIUM HYDROXIDE, BARIUM HYDROXIDE, STRONTIUM HYDROXIDE, CADMIUM, HYDROXIDE, MAGNESIUM HYDROXIDE AND COBALT HYDROXIDE, IN AN AMOUNT SUFFICIENT TO FURNISH AT LEAST ONE EQUIVALENT OF METAL PER EQUIVALENT OF ACID-HYDROGEN CONTENT IN SAID ACIDIC, PARTIAL ESTER OF PHOSPHORIC ACID. 